Vehicle with vertically movable and vertically pulsating wheels

ABSTRACT

An all-terrain vehicle including centrally pivoted bogies on opposite sides of the vehicle body, a primary yoke mounted on the vehicle body and extending crosswise to the vehicle body for coupling the bogies to each other, a secondary yoke mounted on the vehicle body and connected to the vehicle body by hydraulic cylinders at opposite ends thereof, and a selectively actuatable clutch for coupling the secondary yoke to the primary yoke so as to cause the hydraulic cylinders to drive both yokes a desired amount to positively move the bogies to a desired position, and hydraulic circuitry coupled to the hydraulic cylinders for applying a pulsating action to the bogies which is transmitted to the vehicle wheels mounted on opposite ends of the bogies for increasing traction of the wheels on surfaces such as snow, ice, mud and sand. The pulsating action can be applied either when the bogies have been moved to and maintained in a predetermined position or when the bogies are freely pivoting as the vehicle is passing over terrain. A conventional vehicle which includes structure for vertically pulsating individual wheels and changing their elevation relative to the vehicle body.

This is a division, of application Ser. No. 08/521,546 filed Aug. 30,1995 now U.S. Pat. No. 5,797,607.

BACKGROUND OF THE INVENTION

The present invention relates to an all-terrain vehicle and to aconventional vehicle which includes structure for selectively raising orlowering the vehicle wheels to a selectable height to pass over anobstruction and/or for producing a pulsating motion of selectivelyvariable frequency and amplitude to improve traction on various surfacesincluding but not limited to mud, sand, snow and ice.

By way of background, in prior U.S. Pat. No. 4,964,480, an all-terrainvehicle is disclosed wherein pivotal bogies on opposite sides of thevehicle each have a pair of wheels mounted on opposite ends thereof. Thebogies are interconnected by a cross link or yoke so that the pivotingof each link is transmitted to the other link to thereby simultaneouslyraise or lower diagonally opposite wheels. However, the pivoting of thebogies is effected only by the wheels traveling over the ground. Thereis no structure for positively pivoting the bogies to cause any one ofthe wheels mounted on opposite ends thereof to be raised or lowered to aselectable height to pass over obstruction. Furthermore, there is noteaching of imparting a pulsating motion of selectable frequency andamplitude to the wheels to improve traction on all surfaces such assnow, ice, mud and sand.

SUMMARY OF THE INVENTION

It is one object of the present invention to provide a vehicle in whicha vertical pulsating motion can be applied to the vehicle wheels toimprove traction on various surfaces including but not limited to mud,sand, snow and ice.

Another object of the present invention is to provide a vehicle in whicha wheel can be selectively raised to a desired height to pass over anobstruction which is blocking it.

Yet another object of the present invention is to provide a vehicle inwhich a vehicle wheel can not only be raised to a selectable height topass over an obstruction, but also a vertical pulsating motion can alsobe applied to the vehicle wheels after the wheel has been raised toimprove traction.

A further object of the present invention to provide an improvedall-terrain vehicle having centrally mounted bogies on opposite sidesthereof each carrying wheels at opposite ends thereof with the bogiesbeing interconnected by a cross link or yoke and having a motor forpivoting the yoke to positively raise one of the wheels to a selectableheight for passing over an obstruction. Other objects and attendantadvantages of the present invention will readily be perceived hereafter.

The present invention relates to a vehicle comprising a body, aplurality of wheel supports on said body, a plurality of wheels on saidwheel supports, and selectively actuatable pulsating motor means coupledbetween said body and at least one of said wheel supports for pulsatingat least one of said wheels in a vertical direction.

The present invention also relates to a vehicle comprising a body, aplurality of wheel supports on said body, a plurality of wheels on saidwheel supports, and motor means for selectively substantiallysimultaneously pulsating certain of said wheels in a vertical directionand simultaneously changing their elevation relative to said body.

The present invention also relates to a vehicle comprising a body,bogies each having a first central portion and first outer end portionswith said first central portions of said bogies pivotally mounted onopposite sides of said body for free pivotal movement, wheels mounted onsaid first outer end portions of said bogies, said free pivotal movementof said bogies occurring as said wheels mounted thereon follow theterrain, a standard on said body, a yoke having a second central portionand second outer end portions with said second central portion pivotallymounted on said standard and said yoke extending crosswise of said body,elongated links having first and second ends, first connecting meansmovably connecting said second outer end portions of said yoke to saidfirst ends of said elongated links, second connecting means movablyconnecting said first outer ends of said bogies to said second ends ofsaid elongated links, and selectively actuatable motor means forpositively pivoting said yoke to thereby positively pivot said bogiescoupled to said yoke.

The present invention also relates to a vehicle comprising a body,bogies each having a first central portion and first outer end portionswith said first central portions of said bogies pivotally mounted onopposite sides of said body for free pivotal movement, wheels mounted onsaid first outer end portions of said bogies, said free pivotal movementof said bogies occurring as said wheels mounted thereon follow theterrain, a standard on said body, a yoke having a second central portionand second outer end portions with said second central portion pivotallymounted on said standard and said yoke extending crosswise of said body,elongated links having first and second ends, first connecting meansmovably connecting said second outer end portions of said yoke to saidfirst ends of said elongated links, second connecting means movablyconnecting said first outer ends of said bogies to said second ends ofsaid elongated links, laterally extending arms at certain of said firstends of said bogies, outer ends on said laterally extending arms locatedsubstantially above certain of said wheels, and said second connectingmeans being located at said outer ends of said laterally extending arms.

The present invention also relates to a vehicle comprising a body,bogies each having a first central portion and first outer end portionswith said first central portions of said bogies pivotally mounted onopposite sides of said body for free pivotal movement, wheels mounted onsaid first outer end portions of said bogies, said free pivotal movementof said bogies occurring as said wheels mounted thereon follow theterrain, a standard on said body, a yoke having a second central portionand second outer end portions with said second central portion pivotallymounted on said standard and said yoke extending crosswise of said body,elongated links having first and second ends, first connecting meansmovably connecting said second outer end portions of said yoke to saidfirst ends of said elongated links, second connecting means movablyconnecting said first outer ends of said bogies to said second ends ofsaid elongated links, and wherein said vehicle includes first and secondends, and wherein said standard is mounted proximate said first end ofsaid body, and wherein said bogies are connected to said first elongatedlinks proximate said first end of said body, a second standard mountedproximate said second end of said body, a second yoke pivotally mountedon said second standard and extending crosswise of said body, outer endportions on said second yoke, second elongated links having first andsecond ends, third connecting means movably connecting said outer endportions of said second yoke to said first ends of said second elongatedlinks, and fourth connecting means movably connecting said bogies tosaid second ends of said second elongated links proximate said secondend of said body.

The various aspects of the present invention will be more fullyunderstood when the following portions of the specification are read inconjunction with the accompanying drawings wherein:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of the improved all-terrain vehicle ofthe present invention;

FIG. 2 is a fragmentary cross sectional view taken substantially alongline 2—2 of FIG. 1 and showing primarily the clutch arrangement forcoupling a secondary yoke to the primary yoke to thereby cause it toraise or lower the wheel mounting bogies which are normally freelypivotable on the vehicle body;

FIG. 3 is a front elevational view of the improved all-terrain vehicletaken substantially in the direction of arrows 3—3 of FIG. 1;

FIG. 4 is a plan view of the all-terrain vehicle of FIG. 1;

FIG. 5 is a schematic view showing the hydraulic circuit for couplingthe secondary yoke to the primary yoke and for driving the secondaryyoke;

FIG. 6 is a schematic view similar to that shown in FIG. 5 and includinga programmable logic controller;

FIG. 7 is a schematic view showing the distribution of the weight of thevehicle on its four wheels when the bogies are freely pivotable on thevehicle body;

FIG. 8 is a schematic view similar to FIG. 7 but showing the vehicleweight transitionally shifted to a pair of diagonal wheels by theactuation of the secondary yoke;

FIG. 9 is a schematic view similar to FIG. 8 but showing the vehicleweight transitionally shifted to the wheels which are diagonallyopposite to the wheels shown in FIG. 8;

FIG. 10 is a further schematic view showing the transitory distributionof the vehicle weight to the vehicle wheels;

FIG. 11 is a side elevational view of an alternate embodiment of thepresent invention wherein both ends of each of the bogies are positivelylinked to the vehicle chassis;

FIG. 12 is an end elevational view taken substantially in the directionof arrows 12—12 of FIG. 11;

FIG. 13 is a front elevational view of still another embodiment of thepresent invention wherein the bogies are extended to connect to the yokeover the approximate center lines of the vehicle wheels;

FIG. 14 is a fragmentary side elevational view taken substantially inthe direction of arrows 14—14 of FIG. 13;

FIG. 15 is a schematic plan view of a vehicle having four independentlysuspended wheels;

FIG. 16 is a fragmentary cross sectional view taken substantially alongline 16—16 of FIG. 15 and showing a suspension which includes structurefor both raising and lowering a wheel as well as applying a pulsationthereto; and

FIG. 17 is an electro-hydraulic schematic showing how the wheelsuspensions can be controlled to provide raising, lowering, or pulsationto the various wheels.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Summarizing briefly in advance, the all-terrain vehicle 10 of thepresent invention is an improvement over the all-terrain vehicledisclosed and claimed in my prior U.S. Pat. No. 4,964,480 dated Oct. 23,1990, which is incorporated herein by reference, thereby obviating thenecessity for a detailed description of various features which can beincluded for operating the vehicle and which are not necessary for anunderstanding of the present invention.

Summarizing further in advance, one embodiment of the improvedall-terrain vehicle 10 of the present invention includes structure forpositively selectively driving the bogies which are otherwise mounted onthe vehicle body for free pivotal movement in following the contour ofthe terrain. This driving action can be effected by causing thediagonally opposite wheels of the vehicle to be simultaneously lifted orlowered to traverse terrain and also by driving the bogies in a verticalpulsating manner to rapidly shift the weight of the vehicle between theopposed diagonal pairs of wheels to thereby facilitate the passage ofthe vehicle across terrain, such as mud, ice, snow or sand, over whichthe vehicle may not otherwise have the desired traction. In anotherembodiment of the invention, structure is provided to causeindependently mounted wheels of a conventional vehicle to be selectivelypulsated vertically to increase traction as well as to be raised orlowered.

The improved all-terrain vehicle 10 includes a vehicle body 11 havingmirror image bogies 12 and 12′ mounted on pivot shafts 13 and 13′,respectively, which extend outwardly from body 11 and which aresupported in frame members 14 and 14′, respectively. Wheels 15 and 15′are mounted on the outer ends of links or bogies 12 and 12′,respectively, on axles 17 and 17′, respectively. The wheels 15 and 15′can be driven by the structure disclosed in prior U.S. Pat. No.4,964,480 which, as noted above, is incorporated herein by reference.

The bogies 12 and 12′ are coupled to each other through a primary yoke19 which is keyed to hollow shaft 20 (FIG. 2) by key 21. Shaft 20 isrotatable in bearing 22 mounted in standard 23 which extends upwardlyfrom vehicle body 11. A nut 24 is threaded onto the end of outer shaft20 to maintain it in assembled relationship relative to standard 23. Athrust bearing 25 is located between standard 23 and primary yoke 19,and a thrust bearing 27 is located between standard 23 and enlargedportion 29 of outer shaft 20. Links 30 and 30′ are coupled between theouter ends 31 and 31′, respectively, of yoke 19 and ends 32 and 32′ ofbogies 12 and 12′, respectively. Links 30 and 30′ include upper balljoints 33 and 33′, respectively, which are suitably coupled to outerends 31 and 31′, respectively, of yoke 19. Links 30 and 30′ also includeball joints 34 and 34′, respectively, which are coupled to bogies 12 and12′, respectively. Links 30 and 30′ include shock absorbers 35 and 35′which are encircled by springs 37 and 37′, respectively. The ends ofsprings 37 bear against collars 39 and 40 associated with ball joints 33and 34, respectively, and the ends of spring 37′ bear against collars39′ and 40′ associated with ball joints 33′ and 34′, respectively. Thus,the ends 32 and 32′ of bogies 12 and 12′, respectively, are resilientlycoupled to the outer ends 31 and 31′ of primary yoke 19 which ispivotally mounted on standard 23. By virtue of the fact that the bogies12 and 12′ are freely pivotally mounted on pivot shafts 13 and 13′,respectively, the bogies will pivot as the vehicle traverses uneventerrain, and the diagonally opposite wheels on the bogies will eithersimultaneously rise or fall relative to the vehicle body, as fullydisclosed in the above-mentioned U.S. Pat. No. 4,964,480.

There are certain circumstances wherein it is desirable to positivelyraise or lower one of the four vehicle wheels 15 or 15′ to pass over anobstacle, such as a wall, which the wheel otherwise could not climb. Tothis end a secondary yoke 41 is provided for selective coupling toprimary yoke 19, and an hydraulic circuit is provided for drivingsecondary yoke 41 to drive primary yoke 19 to thereby positively pivotbogies 12 and 12′ to thereby raise a desired one of the vehicle wheels.More specifically, secondary yoke 41 is keyed to inner shaft 42 (FIG. 2)by key 43, and secondary yoke 41 is secured on inner shaft 42 by nut 44.A spacer 45 is positioned between primary yoke 19 and secondary yoke 41.A bearing 46 is located between shafts 20 and 42.

The housing 47 of hydraulic clutch 48 is securely mounted on enlargedportion 29 of outer shaft 20 by a plurality of bolts 49 (only oneshown). A plurality of annular discs 50 are keyed for axial but notrotary movement on housing 47 and are interdigitated with a plurality ofdiscs 51 keyed for axial but not rotary movement on inner shaft 42. Anut 56 and a spacer 58 retain discs 51 on shaft 42. Normally discs 50and 51 are not in driving contact with each other by virtue of the factthat pressurized hydraulic fluid is conducted by conduit 52 into chamber53 to thereby move piston 54 to the right against the bias of aplurality of circumferentially spaced springs 55, only one of which isshown. Thus, outer shaft 20 can pivot freely relatively to inner shaft42 because discs 50 and 51 are not forced into engagement with eachother. However, when hydraulic pressure is relieved in conduit 52,springs 55 will expand to force discs 50 and 51 into firm contact witheach other to thereby cause outer shaft 20 and inner shaft 42 to pivotin unison. A clutch of this type is commercially available and is knownas a STROMAG SHB Multiple Disc Hydraulic Brake manufactured by Stromag,Inc. of Dayton, Ohio. While a specific type of hydraulic clutch has beendepicted, it will be appreciated that any type of clutch whichselectively couples and decouples outer shaft 20 and inner shaft 42 canbe used.

An hydraulic circuit is schematically shown in FIG. 5 for selectivelycoupling and uncoupling the primary yoke 19 and secondary yoke 41, andthis hydraulic circuit can be used to selectively pivot bogie 12 in aclockwise or counterclockwise direction to thereby raise the front wheel15 or the rear wheel 15, respectively, while simultaneously lowering thefront wheel 15′ and raising the rear wheel 15′, respectively, bysimultaneously causing the pivoting of the bogie 12′ in acounterclockwise or clockwise direction, respectively, as viewed fromFIG. 1.

The hydraulic circuit of FIG. 5 operates in the following manner. Thepump 57 operates at all times to conduct hydraulic fluid from sump 59through conduit 60 and normally open valve 61 into conduit 62 leading tohydraulic clutch 48 to thereby cause discs 50 and 51 to be separated,which, in turn, permits primary yoke 19 to freely pivot in response tothe pivotal movement of bogies 12 and 12′ and it is not coupled tosecondary yoke 41. At this time the hydraulic fluid will also pass fromconduit 60 through conduit 63 to valve 64 which is in a neutralposition, to thereby cause the hydraulic fluid to pass into conduit 68leading to relief valve 58 and sump 59, and at this time the ends ofconduits 73 and 82 will be blocked at valve 64. When the lever 69 ofvalve 61 is placed in an off position, the flow of hydraulic fluidthrough conduit 60 to conduit 62 will be terminated, and conduit 62leading from hydraulic clutch 48 will be placed in communication withconduit 70 leading to sump 59, thereby causing springs 55 to activateclutch 48 to couple shafts 20 and 42 to couple yokes 19 and 41.

One end of secondary yoke 41 is pivotally connected at 77′ to piston rod77 of cylinder 71 which is pivotally connected to vehicle body 11 at71′, and the opposite end of yoke 41 is pivotally connected at 79′ topiston rod 79 of cylinder 72 which is pivotally connected to vehiclebody 11 at 72′.

When it is desired to positively drive the bogies 12 and 12′, lever 69is manipulated to terminate the flow of pressurized hydraulic fluid toclutch 48 and lever 65 is manipulated to provide pressurized hydraulicfluid to cylinders 71 and 72. In this respect, if it is desired to causesecondary yoke 41 to pivot in a clockwise direction in FIG. 5, the lever65 is moved to a position whereby pressurized hydraulic fluid will flowfrom conduit 63 to conduit 82 and to conduits 74 and 75. This will causepiston rod 77 to move upwardly and piston rod 79 to move downwardly,thereby pivoting secondary yoke 41 in a clockwise direction. As notedabove, at the same time the clutch 48 is engaged so that the clockwiserotation of secondary yoke 41 will cause clockwise rotation of primaryyoke 19 which in turn will drive the front end of bogie 12 downwardlyand raise the front end of bogie 12′. While pressurized fluid is beingsupplied to cylinders 71 and 72 through conduits 74 and 75,respectively, hydraulic fluid is being exhausted from cylinders 71 and72 through conduits 80 and 81, respectively, which feed into conduit 73which valve 64 places in communication with conduit 67 leading back tosump 59.

The hydraulic cylinders 71 and 72 are actuated by lever 65 for as long atime as is required to raise the front end of bogie 12 and the rear endof bogie 12′ to any desired height, and when the bogies 12 and 12′ reachtheir desired position, valve 64 can be placed in a neutral position, asshown in FIG. 5, wherein it blocks flow from conduits 73 and 82 so thatthe bogies remain locked in such a position. At this time hydraulicliquid from conduit 63 flows into conduit 68 leading to the sump 59. Atthis time valve 61 remains in a position to cause clutch 48 to lockyokes 19 and 41 together to maintain the bogies 12 and 12′ to theposition to which they have been moved.

When it is desired to pivot secondary yoke 41 in a counterclockwisedirection in FIG. 5, lever 65 of valve 64 is moved to a position whereinconduit 63 leading from pump 57 is placed in communication with conduit73 which in turn supplies cylinder 71 with hydraulic fluid throughconduit 80 and supplies cylinder 72 with hydraulic fluid through conduit81 while at the same time permitting conduits 75 and 74 to exhaustcylinders 72 and 71, respectively, through conduit 82, valve 64 andconduit 67. It can thus be seen that the bogies 12 and 12′ can be eachpivoted clockwise or counterclockwise by proper manipulation of valve64. As noted above, when the bogies 12 and 12′ reach their desiredposition, valve 64 is returned to a neutral position. At this timeclutch 48 remains activated to maintain the bogies in the position towhich they have been moved.

The foregoing description of the hydraulic circuit of FIG. 5 indicatedhow bogies 12 and 12′ can be pivoted to any desired position eitherclockwise or counterclockwise and then held in such position to permitany one of the four wheels to be raised to a level wherein it can riseabove an obstruction which would normally block it, such as a high wall.After the obstacle has been surmounted, the yokes 19 and 41 can beuncoupled by returning valve 61 to a position wherein hydraulic fluid isconducted from conduit 60 to conduit 62 to deactivate clutch 48 tothereby permit bogies 12 and 12′ to pivot freely, and any pivotal motiontransmitted to yoke 19 will not be transmitted to yoke 41. Also, at thistime after yokes 19 and 41 have been uncoupled, valve 64 can be actuatedto drive yoke 41 back to a central horizontal position in FIG. 5 so thatit can be pivoted an equal amount in either opposite direction formoving the bogies after it has been moved to the central horizontalposition.

Whenever the clutch 48 is actuated to couple yokes 19 and 41, the lever65 of valve 64 can be manipulated in a rapid manner between its twoactuating positions to alternately provide pressurized hydraulic fluidand exhaust to the upper and lower portions of cylinders 71 and 72. Thealternate application of pressurized fluid to the upper and lowerchambers of cylinders 71 and 72 in a rapid manner in any position towhich bogies 12 and 12′ have been moved will rapidly shift the weight ofthe vehicle among the four wheels to cause the wheels to produce avertical pulsating action on their supporting terrain to thus provideimproved traction over surfaces such as ice, mud, sand and snow.

If it is desired to apply a vertical pulsating action to the wheels 15and 15′ while permitting the wheels to follow the terrain, the valve 61can be shifted rapidly between clutch actuating and deactuatingpositions simultaneously with the rapid shifting of valve 64 between itstwo actuating positions so that the bogies can pivot freely when theyokes 19 and 41 are not coupled. In this manner there will be a combinedability of the four wheels to follow the terrain while at the same timereceiving a vertical pulsating action which improves traction. Theamplitude and frequency of the pulsations is achieved by the speed ofmanipulating valve 64.

By way of further explanation, FIG. 7 schematically shows a 2,000 poundvehicle of the type depicted in FIG. 1 in normal operation wherein theweight is distributed equally to each of the four wheels so that eachwheel bears 500 pounds of the load. However, by virtue of the mode ofoperation wherein the weight of the 2,000 pound vehicle is rapidlyshifted, the weight can be momentarily shifted to a pair of diagonallyopposite wheels such that the lower left and upper right wheel each bear1,000 pounds of the load while the opposite diagonal set of wheels bearno load, as shown in FIG. 8. Thereafter, the weight of the vehicle canbe momentarily shifted to the opposite set of diagonal wheels, as shownin FIG. 9, so that each wheel of such opposite set bears a load of 1,000pounds while the opposite diagonal wheels carry no load. It will beappreciated that the foregoing shifting of weight can be rapid andmomentary so that there can be numerous weight shiftings per minute. Itcan thus be seen that improved traction can be obtained by periodicallycausing alternate wheels to bear greater loads and alternate wheels tobear lesser loads, thereby permitting the wheels which bear greaterloads to dig into the ground more positively while permitting theopposite wheels which carry lesser loads to ride more lightly along thesurface of the ground on which the vehicle is traveling. In FIG. 10another position is shown wherein the weight distribution is 750 poundson each of one set of diagonal wheels and 250 pounds on each of anotherset of diagonal wheels. This represents a loading of the vehicle wheelsin passing to the ultimate loading depicted in FIGS. 8 and 9 or it canbe the ultimate loading which the vehicle wheels have if the shifting ofthe weight is sufficiently rapid so that the ultimate loading of FIGS. 8and 9 is never reached. It is possible to shift the weight in anycombination up to and including the ultimate loading of FIGS. 8 and 9.This process of shifting partial weights does not have to be rapid,although it can be, and any distribution of weights can be sustained forany length of time. Thus, by utilizing different combinations of weightshiftings, improved traction can be effected on practically infinitesoil, snow and ice conditions. The foregoing procedure is applicablewith regard to the all-terrain embodiment and the conventional vehicleembodiment described hereafter.

In FIG. 6 a modified embodiment of the hydraulic circuit of FIG. 5 isshown wherein the only difference is that the action of the hydrauliccircuit is governed by a properly programmed commercially availableprogrammable logic controller 90 which is coupled to valve 64 by lead 91and is coupled to valve 61 by lead 92 to selectively activate solenoids88 and 98, respectively, associated with these valves to cause them tomove to the above-described positions for the above-described purposesas desired. The numerals applied to FIG. 6 which are identical to thoseapplied to FIG. 5 represent identical elements of structure, except asnoted above. It will be appreciated that the programmable logiccontroller 90 constitutes a state-of-the-art device, and the programneed not be described in detail other than to state that it can causethe various parts to perform the ultimate functions discussed in detailabove.

In FIGS. 11 and 12 a modified construction of the vehicle is shown. Theall-terrain vehicle 10′ of FIGS. 11 and 12 can possess all of thestructure and operate in an identical manner to the preceding embodimentdescribed with respect to FIGS. 1-10. Accordingly identical numeralswill be applied to those parts of the all-terrain vehicle 10′ of FIGS.11 and 12 which are identical to those elements of structure of thepreceding figures. The only difference is that bogies 12 a and 12 bdiffer from bogies 12 and 12′, respectively, by virtue of the fact thatadditional structure is provided to positively support the ends of thebogies 12 a and 12 b which are not coupled to standard 23. In thisrespect, a standard 95 extends upwardly from vehicle body 11, and itmounts a yoke 97 having a central portion 99 which is pivotally mountedon block 100 which is vertically slidable in opening 101 and isresiliently maintained in a centered position by springs 102 and 103. Alink 104 has its upper end pivotally coupled to yoke 97 by ball joint105 and it has its lower end coupled to bogie 12 a by ball joint 107. Alink 109 has its upper end coupled to yoke 97 by ball joint 110 and itslower end coupled to bogie 12 b by ball joint 111. By virtue of theforegoing construction, both ends of each of the bogies 12 a and 12 bare positively supported on the vehicle body 11.

In FIGS. 13 and 14 a still further embodiment of the present inventionis disclosed. The all-terrain vehicle 10″ of FIGS. 13 and 14 canincorporate all of the features of all of the preceding figures exceptwhere it differs therefrom. In this respect, the main difference is thatthe bogies 12 c and 12 d are configured so that they have arms 115 and117, respectively, which extend upwardly therefrom with their outer endslocated above the centerlines of the wheels 15 and 15′, respectively.Thus, yoke 19′, which is analogous to yoke 19 of the preceding figures,has to be extended laterally so that its outer ends 119 and 120 arelocated above the centerlines of the vehicle wheels. Links 121 and 122,which are analogous to links 30 and 30′ of FIG. 3, extend between yoke19′ and arms 115 and 117. Ball joints 123 and 124 are located at theopposite ends of link 121, and ball joints 125 and 127 are located atthe opposite ends of link 122. Ball joints 123 and 125 are mounted onthe opposite ends of yoke 19′ and ball joints 124 and 127 connect thelower ends of links 121 and 122, respectively, to the upper ends of arms115 and 117, respectively. Yoke 19′ is mounted on standard 23′ whichextends upwardly from vehicle body 11. Standard 23′ is analogous tostandard 23 of FIGS. 1-4. Hydraulic cylinders 71′ and 72′ are analogousto hydraulic cylinders 71 and 72, respectively, of FIGS. 1-4 except thatthey are of a different size so as to fit into the differentconfiguration of FIGS. 13 and 14. The secondary yoke 41′ is analogous tosecondary yoke 41 of FIGS. 1-4. The primed numerals associated withcylinders 71′ and 72′ and yoke 41′ represent analogous structure denotedby unprimed numerals of FIGS. 1-4, and it is therefore believed that adetailed description of such structure is unnecessary.

In FIGS. 15-17 a modification of the above described system of FIG. 6 isapplied to a normal four-wheeled vehicle such as an automobile or truckwherein the wheels are independently suspended.

In FIG. 15 a vehicle frame 140 is shown on which wheels 141, 142, 143and 144 are independently suspended. Only wheel 141 is shown in FIG. 16,but it will be appreciated that wheels 142-144 can be suspended in asimilar manner or in any other suitable manner. Insofar as pertinenthere, a cylindrical frame 145 is welded to the vehicle frame at 147. Acylindrical plate 149 is guided for vertical movement in frame 147. Astrut 150 is provided below plate 149. The lower portion of strut 150consists of shock absorber 151, the lower portion of which is suitablysecured to the upper portion 152 of arm 153. The upper portion 154 ofshock absorber 151 is suitably secured to plate 149. A spring 155 hasits lower portion secured to shock absorber 151 at 157 and its upperportion bears against bracket 159 which is secured to plate 149. Ahydraulic cylinder 160 has its lower end 161 secured to the upperportion of plate 149, and the piston rod 162 of cylinder 160 terminatesat a rubber ball joint bushing 163 which is mounted on portion 148 offrame 140. The remainder of the linkage coupled between the frame andwheel 141 is conventional and unnumbered.

A hydraulic circuit which is controlled by a suitably programmedprogrammable logic controller 165 controls each of wheels 141, 142, 143and 144 as described hereafter in FIG. 17. The inlet of pump 167 is incommunication with sump 169 through conduit 170. Pump 167 runscontinually, and its outlet can return to sump 169 via conduits 171 and172, relief valve 173, conduit 174 and conduit 175. Hydraulic cylinder160 of FIGS. 15 and 16 is in communication with valve 177 via conduits179 and 180. Valve 177 is the same type of valve as valve 64 shown inFIG. 5 wherein it can either block conduits 179 and 180 or supplycylinder 160 with hydraulic fluid through either conduit 179 or 180while causing the other of these conduits to exhaust the cylinder 160.More specifically, if it is desired to raise wheel 141, valve 177 ismoved to a position wherein there is pressurized fluid flowing fromconduit 171 through conduit 181, valve 177 and conduit 179 to cylinder160 while placing conduit 180 in communication with conduit 182 which isin communication with conduit 175 leading to sump 169. This will causecylinder 160 to rise upwardly on piston rod 162 and lift plate 149 inframe 145 with it and thus lift the wheel 141. When valve 177 isreturned to a central position, the hydraulic fluid will be locked incylinder 160 on opposite sides of the piston therein and thus wheel 141will be maintained in the position to which it was moved by cylinder160. When it is desired to lower wheel 141, valve 177 is moved to aposition wherein it effects communication from conduit 171 throughconduit 181 to conduit 180 while placing conduit 179 in communicationwith conduit 182 leading to conduit 175 which flows to sump 169. Thiswill cause cylinder 160 to be driven downwardly in FIG. 16 and thuscarry plate 149 downwardly to move strut 150 downwardly to thus lowerwheel 141.

Valves 185, 187 and 189 are identical to valve 177. Valve 185 is coupledto a cylinder 190 which controls a strut, such as 150 shown in FIG. 16,which is associated with vehicle wheel 142. Valve 187 is associated witha cylinder 191 which is associated with a strut such as 150 shown inFIG. 16 which is coupled to wheel 144. Valve 189 is associated with acylinder 192 which is coupled to a strut such as 150 shown in FIG. 16which is associated with wheel 143.

If it is desired to raise wheel 142, valve 185 places conduit 193 incommunication with conduit 194 to thereby supply hydraulic fluid tocylinder 190 and thus raise cylinder 190 to lift a plate, such as 149,and thus raise wheel 142. At this time exhaust fluid from cylinder 190will flow through conduit 195, valve 185 and conduit 197 to conduit 175leading to sump 169. Once wheel 142 has reached its desired position,valve 185 is returned to a neutral position wherein it locks thehydraulic fluid on the opposite sides of the piston. When it is desiredto lower wheel 142, valve 185 is placed in a position whereinpressurized hydraulic fluid is supplied to cylinder 190 through conduits194 and 195 while hydraulic fluid is exhausted from cylinder 190 throughconduits 193 and 197.

Cylinder 191 is used to raise and lower wheel 144 which is coupled tocylinder 191 through a strut such as 150 shown in FIG. 16. In thisrespect, when it is desired to raise wheel 144, valve 187 is moved to aposition wherein there is flow of pressurized fluid from conduit 171through conduit 198, valve 187 and through conduit 199 to cylinder 191while fluid is exhausted from cylinder 191 via conduit 200, valve 187and conduit 201. This will cause cylinder 191 to ride upwardly on itspiston and raise wheel 144 with it. When it is desired to lower wheel144, valve 187 is moved to a position wherein there is communicationbetween conduits 198 and 200 to provide pressurized fluid to cylinder191 while fluid is exhausted from cylinder 191 via conduits 199 and 201.As with the above cylinders, when valve 187 is returned to a neutralposition, the hydraulic fluid is locked in cylinder 191 to maintain thewheel 144 to the position to which it was last moved.

When it is desired to raise wheel 143, valve 189 is moved to a positionwherein there is a flow of pressurized fluid through conduit 203, valve189 and conduit 204 to cylinder 192 while fluid is exhausted fromcylinder 192 via conduit 205, valve 189 and conduit 207. This will raisecylinder 192 and also raise wheel 143 which is coupled to cylinder 192through a strut such as 150 shown in FIG. 16. When it is desired tolower wheel 143, valve 189 is moved to a position wherein pressurizedhydraulic fluid is supplied to cylinder 192 via conduit 205 while fluidis exhausted from cylinder 192 via conduits 204 and 207. As with theabove cylinders, when valve 189 is returned to a neutral position, thehydraulic fluid is locked in cylinder 192 to maintain wheel 143 to theposition to which it has been raised or lowered.

It will be appreciated that each of valves 177, 185, 187 and 189 can becontrolled manually to raise or lower diagonal pairs of wheels. Thismanual control may be effected through a mechanical linkage or throughthe programmable logic controller 165 which is coupled to the foregoingvalves through electrical lead lines 210, 211, 212 and 213,respectively, which are coupled to solenoids 214, 215, 216 and 217,respectively. It will thus be appreciated that diagonally oppositewheels can be raised or lowered simultaneously without lowering orraising, respectively, the other pair of diagonally opposite wheels. Forexample, if desired, wheels 142 and 143 may be raised or loweredsimultaneously without in any way affecting wheels 141 and 144. Also, ifdesired, diagonal wheels 141 and 144 can be raised or loweredsimultaneously without affecting wheels 142 and 143.

In addition to the foregoing, the programmable logic controller 165 canactuate the various cylinders to provide vertical pulsations to each ofthe wheels individually or to all of the wheels, simultaneously or toany combination of the wheels, such as possibly vertically pulsatingonly wheels 143 and 144 or only pulsating wheels 141 and 142. Also, apair of diagonally opposite wheels can be pulsated while not pulsatingthe other pair of diagonally opposite wheels. In fact, there can be anycombination of vertical pulsations of the wheels through the action ofthe programmable logic controller which causes the valves controllingeach of the cylinders associated with the wheels to functionaccordingly. In this respect, the pulsation is effected, for example,with valve 177 by rapidly reciprocating it back and forth to rapidlyreverse the flow of hydraulic fluid to cylinder 160. The same wouldoccur with respect to other of the valves 185, 187 and 189.

In addition to the foregoing, the programmable logic controller cancause any of the valves to cause their associated wheels to be raised orlowered while other of the wheels are being vertically pulsated. Thus,for example, it might be desirable to raise wheel 141 while loweringwheel 144 and simultaneously pulsating wheels 143 and 142. Also, it maybe desirable to vertically pulsate one pair of diagonal wheels whilepulsating the other pair of diagonal wheels. Thus, here again, there canbe any combination of raising and lowering of certain wheels whilepulsating other of the wheels.

In addition to the foregoing, vertical pulsating movement can be appliedto any one of the wheels while it is being raised or lowered. Thus, forexample, wheel 141 which is controlled by cylinder 160, can be raisedand pulsated simultaneously by causing valve 177 to intermittently moveto effect raising and intermittently reciprocating valve 177 to effectpulsations. Thus, any one of the wheels can be simultaneously raised andpulsated or lowered and pulsated. Thus, for example, wheel 141 can beraised and pulsated while wheel 144 is lowered and pulsated and whilewheels 142 and 143 are merely pulsated without being raised or lowered.Also, diagonal pairs of wheels can be raised or lowered andsimultaneously vertically pulsated. Also, one pair of diagonal wheelscan be pulsated while the other pair is raised or lowered. Thus, hereagain there are infinite combinations of raising, lowering and pulsatingthe wheels.

While the above description relative to FIGS. 1-6 has shown an hydrauliccircuit for selectively driving the primary yoke 19, it will beappreciated that the motors can be of any type including but not limitedto electric motors and pneumatic motors, and that the clutch can be ofany type including but not limited to electrical, magnetic or mechanicalclutches.

While preferred embodiments of the present invention have beendisclosed, it will be appreciated that the present invention is notlimited thereto but may be otherwise embodied within the scope of thefollowing claims.

What is claimed is:
 1. A vehicle comprising a body, bogies each having afirst central portion and first outer end portions with said firstcentral portions of said bogies pivotally mounted on opposite sides ofsaid body for free pivotal movement, wheels mounted on said first outerend portions of said bogies, said free pivotal movement of said bogiesoccurring as said wheels mounted thereon follow the terrain, a standardon said body, a yoke having a second central portion and second outerend portions with said second central portion pivotally mounted on saidstandard and said yoke extending crosswise of said body, elongated linkshaving first and second ends, first connecting means movably connectingsaid second outer end portions of said yoke to said first ends of saidelongated links, second connecting means movably connecting said firstouter ends of said bogies to said second ends of said elongated links,and selectively actuatable motor means for positively pivoting said yoketo thereby positively pivot said bogies coupled to said yoke to therebymove all of said wheels simultaneously.
 2. A vehicle as set forth inclaim 1 wherein said motor means is hydraulic.
 3. A vehicle as set forthin claim 1 including actuating means associated with said motor meansfor selectively applying a pulsating action to said bogies to effect avertical pulsating action to said wheels.
 4. A vehicle as set forth inclaim 1 wherein said motor means include means for raising a wheel to aselectable height and maintaining said wheel at said height.
 5. Avehicle as set forth in claim 1 including a second yoke pivotallymounted crosswise to said body, and wherein said selectively actuatablemotor means are coupled between said body and said second yoke, andclutch means for selectively coupling said second yoke to said yoke tothereby positively pivot said bogies coupled to said yoke when saidselectively actuatable motor means is actuated.
 6. A vehicle as setforth in claim 1 including a second yoke pivotally mounted crosswise tosaid body, and wherein said selectively actuatable motor means arecoupled between said body and said second yoke, and clutch means forselectively coupling said second yoke to said yoke to thereby positivelypivot said bogies coupled to said yoke when said selectively actuatablemotor means is actuated, and wherein said second yoke includes outerends, and wherein said selectively actuatable motor means comprise firstand second hydraulic cylinders coupled between said outer ends of saidsecond yoke and said body.
 7. A vehicle as set forth in claim 1including a second yoke pivotally mounted crosswise to said body, andwherein said selectively actuatable motor means comprise an hydrauliccylinder coupled between said second yoke and said body.
 8. A vehicle asset forth in claim 1 wherein said vehicle includes first and secondends, and wherein said standard is mounted proximate said first end ofsaid body, and wherein said bogies are connected to said first elongatedlinks proximate said first end of said body, a second standard mountedproximate said second end of said body, a second yoke pivotally mountedon said second standard and extending crosswise of said body, outer endportions on said second yoke, second elongated links having first andsecond ends, third connecting means movably connecting said outer endportions of said second yoke to said first ends of said second elongatedlinks, and fourth connecting means movably connecting said bogies tosaid second ends of said second elongated links proximate said secondend of said body.
 9. A vehicle as set forth in claim 1 wherein saidsecond connecting means are located substantially above certain of saidwheels.
 10. A vehicle as set forth in claim 1 wherein said bogiesinclude laterally extending arms at certain of said first ends of saidbogies, outer ends on said laterally extending arms locatedsubstantially above certain of said wheels, and wherein said secondconnecting means are located at said outer ends of said laterallyextending arms.
 11. A vehicle as set forth in claim 4 includingactuating means associated with said motor means for selectivelyapplying a pulsating action to said bogies.
 12. A vehicle as set forthin claim 5 wherein said second yoke includes outer ends, and whereinsaid selectively actuatable motor means comprise first and secondhydraulic cylinders coupled between said outer ends of said second yokeand said body.
 13. A vehicle as set forth in claim 12 including meansfor causing said first and second cylinders to apply a pulsating actionto said second yoke to apply a pulsating action to said bogies to effecta vertical pulsating action to said wheels.
 14. A vehicle as set forthin claim 12 including a hydraulic circuit coupled to said first andsecond hydraulic cylinders for actuating said first and second cylindersto pivot said bogies for moving one of the wheels mounted thereon to adesired position.
 15. A vehicle as set forth in claim 6 including meansfor causing said first and second cylinders to apply a pulsating actionto said second yoke to apply a pulsating action to said bogies to effecta vertical pulsating action to said wheels.
 16. A vehicle as set forthin claim 15 including a hydraulic circuit coupled to said first andsecond hydraulic cylinders for actuating said first and second cylindersto pivot said bogies for moving one of the wheels mounted thereon to adesired position.
 17. A vehicle as set forth in claim 7 including meansfor causing said hydraulic cylinder to apply a pulsating action to saidsecond yoke to apply a pulsating action to said bogies to effect avertical pulsating action to said wheels.
 18. A vehicle as set forth inclaim 7 including a hydraulic circuit coupled to said hydraulic cylinderfor actuating said hydraulic cylinder to pivot said second yoke formoving one of the wheels mounted on one of said bogies to a desiredposition.
 19. A vehicle as set forth in claim 8 wherein said second yokeis also resiliently mounted for vertical movement on said secondstandard.
 20. A vehicle comprising a body, bogies each having a firstcentral portion and first outer end portions with said first centralportions of said bogies pivotally mounted on opposite sides of said bodyfor free pivotal movement, wheels mounted on said first outer endportions of said bogies, said free pivotal movement of said bogiesoccurring as said wheels mounted thereon follow the terrain, a standardon said body, a yoke having a second central portion and second outerend portions with said second central portion pivotally mounted on saidstandard and said yoke extending crosswise of said body, elongated linkshaving first and second ends, laterally extending arms having first andsecond ends, first connecting means movably connecting said second outerend portions of said yoke to said first ends of said elongated links,said first outer ends of said bogies being connected to said first endsof said laterally extending arms, said second ends of said elongatedlinks being connected to said second ends of said laterally extendingarms, and said second ends of said laterally extending arms beinglocated substantially over certain of said wheels.
 21. A vehiclecomprising a body, bogies each having a first central portion and firstouter end portions with said first central portions of said bogiespivotally mounted on opposite sides of said body for free pivotalmovement, wheels mounted on said first outer end portions of saidbogies, said free pivotal movement of said bogies occurring as saidwheels mounted thereon follow the terrain, a standard on said body, ayoke having a second central portion and second outer end portions withsaid second central portion pivotally mounted on said standard and saidyoke extending crosswise of said body, elongated links having first andsecond ends, first connecting means movably connecting said second outerend portions of said yoke to said first ends of said elongated links,second connecting means movably connecting said first outer ends of saidbogies to said second ends of said elongated links, and wherein saidvehicle includes first and second ends, and wherein said standard ismounted proximate said first end of said body, and wherein said bogiesare connected to said first elongated links proximate said first end ofsaid body, a second standard mounted proximate said second end of saidbody, a second yoke pivotally mounted on said second standard andextending crosswise of said body, outer end portions on said secondyoke, second elongated links having first and second ends, thirdconnecting means movably connecting said outer end portions of saidsecond yoke to said first ends of said second elongated links, andfourth connecting means movably connecting said bogies to said secondends of said second elongated links proximate said second end of saidbody.
 22. A vehicle comprising a body, bogies each having a firstcentral portion and first outer end portions with said first centralportions of said bogies pivotally mounted on opposite sides of said bodyfor free pivotal movement, wheels mounted on said first outer endportions of said bogies, said free pivotal movement of said bogiesoccurring as said wheels mounted thereon follow the terrain, a yokehaving a second central portion and second outer end portions with saidsecond central portion pivotally mounted on said body and said yokeextending crosswise of said body, elongated links movably connectingsaid yoke to said bogies, and a selectively actuatable motor effectivelycoupled to said yoke for pivoting said bogies to thereby move all ofsaid wheels simultaneously.
 23. A vehicle as set forth in claim 22wherein said motor is hydraulic.
 24. A vehicle as set forth in claim 22including a pulsator member coupled to said motor.
 25. A vehicle as setforth in claim 22 wherein said actuatable motor drives said bogies toraise a wheel to a selectable height and maintain said wheel at saidheight.
 26. A vehicle as set forth in claim 22 including a second yokepivotally mounted crosswise to said body, and wherein said selectivelyactuatable motor is coupled between said body and said second yoke, anda clutch selectively coupling said second yoke to said yoke to therebypositively pivot said bogies coupled to said yoke when said selectivelyactuatable motor is actuated.
 27. A vehicle as set forth in claim 22including a pivotable member mounted on said body, and wherein saidselectively actuatable motor is coupled between said body and saidpivotable member, and a clutch selectively coupling said pivotablemember to said yoke, and wherein said pivotable member includes an outerend, and wherein said selectively actuatable motor comprises anhydraulic cylinder coupled between said outer end of said pivotablemember and said body.
 28. A vehicle as set forth in claim 22 including apivotable member mounted on said body, and wherein said selectivelyactuatable motor is coupled between said pivotable member and said body.29. A vehicle as set forth in claim 22 wherein said body includes firstand second ends, and wherein said yoke is mounted proximate said firstend of said body, a second yoke pivotally mounted proximate said secondend of said body, and connected to said bogies.
 30. A vehicle as setforth in claim 22 wherein said yoke is connected to said bogiessubstantially above certain of said wheels.
 31. A vehicle as set forthin claim 22 wherein said bogies include laterally extending arms, outerends on said laterally extending arms located substantially abovecertain of said wheels, and wherein said yoke is connected to said outerends of said laterally extending arms.
 32. A vehicle as set forth inclaim 25 including a pulsator member coupled to said motor.
 33. Avehicle as set forth in claim 26 wherein said second yoke includes outerends, and wherein said selectively actuatable motor comprises first andsecond hydraulic cylinders coupled between said outer ends of saidsecond yoke and said body.
 34. A vehicle as set forth in claim 33including a pulsator member coupled to said first and second cylinders.35. A vehicle as set forth in claim 33 including a hydraulic circuitcoupled to said first and second hydraulic cylinders for actuating saidfirst and second cylinders to pivot said bogies for moving one of thewheels mounted thereon to a desired position.
 36. A vehicle as set forthin claim 27 including a pulsator member coupled to said hydrauliccylinder.
 37. A vehicle as set forth in claim 36 including a hydrauliccircuit coupled to said hydraulic cylinder for actuating said cylinderto pivot said bogies for moving one of the wheels mounted thereon to adesired position.
 38. A vehicle as set forth in claim 28 including apulsator member for causing said selectively actuatable motor to apply apulsating action to said pivotable member to apply a pulsating action tosaid bogies to effect a vertical pulsating action to said wheels.
 39. Avehicle as set forth in claim 28 including an actuating circuit foractuating said selectively actuatable motor for pivoting said pivotablemember.
 40. A vehicle as set forth in claim 29 wherein said second yokeis resiliently mounted for vertical movement on said body.
 41. A vehiclecomprising a body, bogies each having a first central portion and firstouter end portions with said first central portions of said bogiespivotally mounted on opposite sides of said body for free pivotalmovement, wheels mounted on said first outer end portions of saidbogies, said free pivotal movement of said bogies occurring as saidwheels mounted thereon follow the terrain, a yoke having a secondcentral portion and second outer end portions with said second centralportion pivotally mounted on said body and said yoke extending crosswiseof said body, laterally extending arms having inner ends connected tocertain end portions of said bogies, outer ends on said laterallyextending arms located substantially over certain of said wheels, andsaid yoke being connected to said outer ends of said laterally extendingarms.
 42. A vehicle comprising a body, bogies each having a firstcentral portion and first outer end portions with said first centralportions of said bogies pivotally mounted on opposite sides of said bodyfor free pivotal movement, wheels mounted on said first outer endportions of said bogies, said free pivotal movement of said bogiesoccurring as said wheels mounted thereon follow the terrain, a firstyoke having a second central portion and second outer end portions withsaid second central portion pivotally mounted on said body and saidfirst yoke extending crosswise of said body, first connections betweensaid first yoke and said bogies, said vehicle including first and secondends, and wherein said first yoke is mounted proximate said first end ofsaid body, and wherein said bogies are connected to said first yokeproximate said first end of said body, a second yoke pivotally mountedproximate said second end of said body and extending crosswise of saidbody, second connections between said second yoke and said bogies, and aselectively actuatable motor effectively connected to said first yoke.43. A vehicle comprising a body, elongated members pivotally mounted onopposite sides of said body for free pivotal movement, an outer endportion on each of said elongated members, a wheel mounted on said outerend portion of each of said elongated members, said free pivotalmovement of said elongated members occurring as said wheels mountedthereon follow the terrain, a linkage mounted on said body and movablyconnected to said elongated members, a programmable logic controller,and a selectively actuatable motor effectively coupled relative to saidprogrammable logic controller and said linkage for moving said elongatedmembers.
 44. A vehicle as set forth in claim 43 wherein saidprogrammable logic controller causes said linkage to pulsate saidelongated members.
 45. A vehicle as set forth in claim 43 wherein saidprogrammable logic controller causes said actuatable motor to drive atleast one of said elongated members to raise a wheel to a selectableheight and maintain said wheel at said height.
 46. A vehicle as setforth in claim 45 wherein said programmable logic controller causes saidlinkage to pulsate said elongated members.
 47. A vehicle comprising abody, bogies each having a central portion and outer end portions withsaid central portions of said bogies pivotally mounted on opposite sidesof said body for pivotal movement, wheels mounted an said outer endportions of said bogies, a programmable logic controller, and meanscoupling said programmable logic controller to a pulsatable linkageconnecting said first and second bogies.
 48. A vehicle comprising abody, bogies each having a central portion and outer end portions withsaid central portions of said bogies pivotally mounted on opposite sidesof said body for pivotal movement, wheels mounted on said outer endportions of said bogies, a linkage connecting said bogies, and a motorfor pivoting said bogies in opposite directions through said linkage tomove all of said wheels simultaneously.
 49. A vehicle comprising a body,bogies each having a central portion and outer end portions with saidcentral portions of said bogies pivotally mounted on opposite sides ofsaid body for pivotal movement, wheels mounted on said outer endportions of said bogies, said pivotal movement of said bogies occurringas said wheels mounted thereon follow the terrain so that diagonallyopposite ends of said bogies simultaneously move in the same direction,a linkage coupled to each of said bogies and a motor coupled to saidlinkage for pulsating all of said wheels simultaneously.